Rolling mill crown prevention and control means

ABSTRACT

A ROLLING MILL HAVING MEANS UTILIZING THE ROLLING LOAD TO CONTROL THE CROWN OF THE ROOLS. A BEAM IN CONJUNCTION WITH ASSOCIATED STRUCTURE IS ARRANGED TO RECEIVE THE ROOLING LOAD AND DIRECT IT TO THE OUTBOARD BEARINGS OF THE BACKUP ROLLS SO AS TO CONTROL THE CROWN OF THE ROOLS, THE ARRANGEMENT BEING SUCH THAT NO CROWN CONTROLLING LOAD IS APPLIED TO THE MILL HOUSING.

NOV; 23, 1971 ElBE ET AL ROLLING MILL CROWN PREVENTION AND CONTROL MEANS Filed 001:. 24, 1968 4 Sheets-Sheet 1 ATTO RN EY NOV. 23, 1971 W E ETAL ROLLING MILL CROWN PREVENTION AND CONTROL MEANS Filed Oct. 24, 1968 4 Sheets-Sheet 2 ATTORNEY Nov. 23, 1971 EBE ETAL 3,621,695

ROLLING MILL CROWN PREVENTION AND CONTROL MEANS Filed 001;. 24, 1968 4 Sheets-Sheet 3 INVENTORS NOV... 23, 1971 EIBE ET AL 3,521,695

ROLLING MILL CROWN PREVENTION AND CONTROL MEANS Filed Oct. 24. 1968 4 Sheets-Sheet 4,

BY I p 4 5 V A; (Mg (4n r-1/ ATTORNEY United States Patent O US. Cl. 72-237 14 Claims ABSTRACT OF THE DISCLOSURE A rolling mill having means utilizing the rolling load to control the crown of the rolls. A beam in conjunction with associated structure is arranged to receive the rolling load and direct it to the outboard bearings of the backup rolls so as to control the crown of the rolls, the arrangement being such that no crown controlling load is applied to the mill housing.

BACKGROUND OF THE INVENTION This invention pertains generally to the art of rolling mills and particularly to the means for controlling the crown of the mill rolls so as to maintain the shape and flatness of the metal strip passing through these rolls. It is well known that the shape and flatness of the strip may be maintained by the application of forces to the outboard bearings of the rolls so as to control their crown. By controlling the crown of the rolls it is possible to counteract the eflect of the rolling load which tends to bend the rolls between their supporting bearings.

There have been provided crown controlling devices wherein the crowning force is applied to the outboard bearings of the backup rolls of 4-high mills by the employment of outside forces, which are often very large and are generally applied by hydraulically actuated cylinders connected to the outboard bearings. The reaction forces of this crown controlling load are in some prior art constructions taken up by the mill housing by way of the mill screws. Accordingly, these devices have the disadvantage that the housings must be built excessively large to avoid the possible failure thereof. While there have been provided mills designed to isolate these outside crown controlling loads from the housing by the use of a beam member arranged between the bearings of the mils and the housing, these mills have the disadvantage that they still require the use of external forces to achieve the crown control.

SUMMARY OF THE INVENTION The present invention provides a crown prevention and control means which utilizes the rolling load itself to counter-bend the mill rolls and to control the crown thereof so as to achieve a flat strip. The means in accordance with the invention involves the provision of an adjustable mechanism which controls the application of the rolling load to the outboard bearings of the rolls so as to prevent roll deflection. Since no crowning force is produced in the absence of a rolling load, the system in accordance with the invention could be described more properly as a self-energizing roll stiffening system.

The crown prevention and control means in accordance with the invention is an improvement over the prior devices since it eliminates the need for the use of any outside forces and therefore there is no excessive load on the mill housing. Moreover, the system in accordance with the invention is easily adjusted to achieve two-way crownmg.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation of a 4-high mill constructed in accordance with the present invention;

3,621,695 Patented Nov. 23, 1971 FIG. 2 is an end view of the mill shown in FIG. 1;

FIG. 3 is an essentially diagrammatic illustration of the mill shown in FIGS. 1 and 2; and

FIGS. 4, 5, 6, 7 and 8 are diagrammatic illustrations of modified forms of mill construction in accordance with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, there is shown a 4-high mill comprising the usual spaced housings 10 and 12 which extend vertically and have formed therein rectangular windows 14 and 16, respectively. The windows 14 and 16 slidably receive the bearing chocks of the work rolls 18 and 20 and the backup rolls 22 and 24, the rolls being arranged in the usual manner of a 4-high mill with each of the smaller diameter work rolls being backed up by a larger diameter backup roll as is apparent from FIG. 1. The work rolls 18 and 20 have their journals received in bearing chocks 26 and 28, respectively. The backup rolls 22 and 24 have their journals received in bearing chocks 30 and 32, respectively. The work rolls are driven by means of couplings 34 and 36 at their ends in the usual manner. There also may be provided conventional means (not shown) for biasing the work rolls toward a separated position by means of hydraulic pressure acting on the hearing chocks thereof.

The portion of the mill thus far described is entirely conventional wherefore there is no necessity for any more detailed description.

At the upper portion of the mill there is provided a beam 40 which extends horizontally above the backup roll 22 and which has a generally hollow-like cross-section, as is best illustrated in FIG. 2. The beam 41} extends through and outwardly of the windows 14 and 16 and has portions located adjacent the upper end of each of the chocks 30, such portions being provided with rocker plates 42 which cooperate with rocker plates 44 on the adjacent portions of the chocks 30.

The beam 40 and the chocks 30 are connected together for conjoint vertical movement by means of cooperating projections 46 and 48 on the lower portion of the beam 40 and the upper portion of the chocks 30, respectively, as is best shown in FIG. 2.

Mounted within the hollow of the beam 40 are a pair of rocker arms 50. The rocker arms 50 are located relative to the beam 40 by means of mounting screws 51 which threadedly engage the sides of the rocker arms 50 and have their heads projected int-o oblong holes 53 in the vertical side walls 41 of the beam 410.

For simplicity, only the left rocker arm, as viewed in FIG. 1, will be described in detail, it being noted that the other rocker arm is similarly constructed and provided with similar cooperating parts. This rocker arm 50 has its inner end held between opposed horizontal wall portions of the beam 40 by means of a pair of hydraulically actuated piston-cylinder means :52 and 54. It will be apparent by consideration of FIG. 1 that the inner end of the rocker arm 50 may be held in a desired fixed position relative to the beam 40 by controlling the application of hydraulic pressure to the two cylinder means 52 and 54. The purpose of this arrangement will be described more fully hereafter.

The outer end of the rocker arm 50 has a link 56 pivotally mounted thereon by means of a pin 58. The link 56 is pivotally positioned by means of a hydraulic actuating cylinder 60 mounted on the rocker arm 50 and having the outer end of its actuating rod pivotally secured to the link 56.

The lower end of the link 56 is provided with a hook portion 62 which is engaged with a cooperating hook portion 64 provided on an outboard journal bearing 66 provided on the outer end of the backu roll 22. Each of the ends of the backup rolls 22 is provided with extended end portions 23 located outwardly of the bearing chocks and being received in journal bearings 66 which are provided with hook portions 64.

At a medial portion of the rocker arm 50 there is provided a vertical bore 70 in its upper side. Mounted within the bore 70 is a breaker block assembly 72 having a spherical upper surface which contacts a conforming spherical surface formed on the bottom end of the usual mill screw 74, which is threadedly received in a nut 75 in the mill housing. It will be noted that the mill screw 74 is aligned with the rocker blocks 42 and 44.

A movable rocker block assembly 80 is positioned between an upper surface portion 82 of beam 40 and a bottom surface portion 84 f rocker arm 50. The rocker block assembly 80 comprises a block containing member 86 contacting the surface 84, a lower rocker block 88 contacting the surface 82 and an upper rocker block 90 positioned between rocker block 88 and member 86. The rocker blocks 88 and 90 cooperate at cylindrical surfaces and are contained within the member 86 for conjoint movement therewith as is shown in FIG. 1.

Means are provided for moving the rocker block assembly 80 horizontally to various positions between the surfaces of the beam and the rocker arm 50. To this end, a horizontally extending recess 92 is formed in the bottom side 84 of rocker arm 50. Extending within the recess 92 is the actuator arm 94 of a hydraulic actuator cylinder 96 mounted on the rocker arm 50 by suitable brackets. The extended end of arm 94 is pivotally secured to an upwardly projecting bracket portion 95 of member 86, this portion extending upwardly from member 86 into the recess 92. By this arrangement, the actuation of the hydraulic cylinder 96 to extend or retract the actuating arm 94 will serve to position the rocker block assembly 80 at various locations ofiset laterally with respect to vertical axis of the mill screw 74.

At a central location, the beam 40 is secured to a pair of upright rods 100. The upper ends of the rods 100 are secured to a horizontally extending plate 102 which is urged upwardly by a cylinder assembly 104 which is mounted on a housing 106 separating the housings and 12. The cylinder assembly 104 thus urges the beam 40, and the chocks of the backup roll 22, upwardly to thereby urge the rocker arm 50 against the mill screw 74 and hold the entire assembly of parts in an upper position limited by the mill screws 74.

The cylinders 52 may serve as a clearance takeup in the event that the cylinder 104 has not raised the assembly completely against the mill screws 74. Pressurization of the cylinders 52 to expand their plungers will serve to take up this clearance.

The right-hand side of the upper portion of the mill is provided with an identical rocker arm 50 and other associated mechanism as was described with respect to the left-hand side of the mill, such parts being indicated by corresponding reference numerals.

It is particularly noted that the beam 40 and the rocker arms 50 are of heavy duty construction so that they will not deflect much under the loads to be applied thereto in the operation of the mill. Thus, these parts serve as rigid load transmitting means in the operation of the mill as will appear hereafter.

At the lower part of the mill, the backup roll 24 is provided with a beam and rocker arm mechanism along with associated structure essentially the same as that described with respect to the upper backup roll 22. Referring to the drawings it will be noted that the corresponding parts have the same reference numerals with the exception that primes have been added.

Thus, there is provided a beam 40 which extends horizontally below the backup roll 24. The beam 40' is provided with portions adjacent the chocks 32 provided with rocker plates 42' which cooperate with rocker plates 44' 4 on the adjacent portions of the chocks 32. The beam 40' and the chocks 32 are connected together by means of cooperating projections constructed similar to the projections 48 on the backup roll 22 or suitable link means.

Mounted within the hollow of the beam 40 are a pair of rocker arms 50' located relative to the beam by means of mounting screws 51. The left-hand rocker arm 50' has its inner end held between opposed horizontal wall portions of the beam 40 by means of a pair of hydraulically actuated piston-cylinder means 52' and 54' which serve to hold the inner end of rocker arm 50' in a desired, fixed position relative to the beam 40.

The outer end of the rocker arm 50' has a link 56 pivotally mounted thereon and positionable by means of an actuating cylinder 60'. The upper end of the link 56 is provided with a hook portion 62 which engages a cooperating hook portion 64 on an outboard journal bearing 66 provided at the outer end of the backup roll 24.

A medial portion of the rocker arm 50' is provided with a vertical bore 70 containing a breaker block 72 having a cylindrical lower surface which contacts a conforming cylindrical surface formed on the bottom end of a rocker plate 73 which rests on the housing 10 of the mill. It will be noted that these rocker blocks are aligned with the rocker plates 42 and 44 and the mill screw 74.

There is provided a moveable block assembly positioned between opposed surface portions 82 and 84' between the beam 40" and the rocker arm 50'. The rocker block assembly 80' comprises a block containing member 86 and a pair of rocker blocks 88' and 90 which cooperate at cylindrical surfaces and are contained in the member 86 for conjoint movement therewith. There is provided means for moving the rocker block assembly 80' horizontally to various positions between the beam 40 and the rocker arm 50'. This means comprises a hydraulically actuated cylinder 96 having an actuator arm 94 extending within a recess 92 for pivotal securement to a bracket portion 95 of member 86. By this arrangement the cylinder 96 will serve to position the rocker block assembly 80 at various locations offset laterally relative to the axis of the blocks 72 and 73.

It will be apparent that the right-hand side of the lower portion of the mill is provided with an identical rocker arm 50' and other associated mechanism similar to that provided on the left-hand side of the mill, such parts being indicated by corresponding reference numerals.

The portion of the mill shown in FIG. 1 comprising the upper backup roll and the essential parts associated therewith are illustrated diagrammatically in FIG. 3. This figure provides a simple illustration of the manner in which the rolling load is distributed to various parts of the mill. Accordingly, the description of the operation of the mill in accordance with the invention will be directed primarily to FIG. 3, although it will be equally applicable to FIGS. 1 and 2.

Referring to FIG. 3, the rolling load is indicated by P and it will be apparent that by reason of the construction of the mill, the mill screws 74 will each receive half of the rolling load, of P/2. Also, from a consideration of this figure, it will be apparent that the links 56 apply a load to the outboard bearings 66 of the backup roll 22 and this load may be considered to be the roll crowning force. Moreover, this roll crowning force is delivered to the links 56 from the rocker plates 42 and 44, through the beam 40 and the rocker block assembly 80 to the rocker arms 50. Thus, this force tends to move the outer portion of the rocker arms 50 upwardly and accordingly the links 56 apply an upward force to the outboard bearings 66 to thereby tend to crown out the backup roll 22. Also, it will be apparent that the roll crowning force is proportional to the rolling load and is dependent on the offset position of the rocker block assembly 80 (distance X in FIG. 3). Thus, the more the rocker block assembly 80 is moved outwardly or offset relative to the mill screws the greater the roll bending force applied through the rocker arm and the links to the outboard bearings. This is because the mill screw serves as the fulcrum for the rocker arm 50 and as the rocker block assembly is moved outwardly, there is an increase of the lever arm of the rolling load applied thereto from the beam 40.

The position of the rocker block assembly 80 for a particular mill will be determined by a consideration of the rolling load, the plate width, the roll body diameter and various other dimensional and structural configurations of the mill itself. However, for a given plate width and roll body diameter, there can be determined a particular location of the assembly 84] which will produce a large enough roll crowning force at the outboard hearings to maintain a flat roll.

It will thus be apparent that the mill construction in accordance with the invention involves a crown preven tion and control system wherein the backup rolls are crowned by utilizing the rolling load to counter-bend the roll and this is accomplished by directing the rolling load through an adjustable mechanism. Moreover, since no roll crowning force is produced in the absence of a rolling load, the system in accordance with the invention may be more properly described as a self-energizing roll stiffening system.

A further advantage of the arrangement in accordance with the invention is that no feedback system is required to correct the loading of the outboard bearings to allow for gauge adjustment or variance in rolling load. The roll crowning force is proportional to the rolling load and as this decreases, the crowning load decreases.

Another feature in accordance with the invention is that a negative crowning action may be achieved simply. Negative crowning is utilized in some mill applications where the rolls have a permanent crown formed thereon and it is necessary to take this crown out under some conditions of operation or to add to this permanent crowning under other conditions of operation. FIG. 8 illustrates how negative crowning may be achieved in accordance with the invention. The form of the invention shown in FIG. 8 is the same as that shown in FIG. 3 except that the parts are constructed and arranged so that the rocker block means 80 may be moved between the solid and dotted line positions shown by the cylinder 96, and the roll 22 is provided with a permanent crown. When the rocker block means 80 is moved to the dotted line position (the offset from screws 74- being indicated by dimension X), or to any position inwardly of the mill screws, a negative crowning load will be applied to the outboard bearings of the roll to urge the same downwardly. Of course, when the rocker block means are moved to any position outwardly of the mill screws (such as is indicated by dimension X), a positive crowning load is applied to the outboard bearings of the roll 22 as was discussed with respect to FIG. 3.

The displacement of rocker block means 80 away from centerline of mill housing will necessarily alter the spring rate of the mill. However, various gauge control systems known in the art will be used to compensate for these variations of spring rate. Moreover, because the system in accordance with the invention achieves crown control by internal means, there is no need to provide an interrelated gauge and crown control system such as would be necessary in prior art systems having automatic crown control. This type of system could be rather complicated. Thus, the construction in accordance with the invention can achieve gauge and crown control automatically by means of a gauge control system alone.

It is to be noted that the problem, which is inherent in all crown controlling mechanisms, of the possible failure of the crowning rolls because of the large crowning forces (such as would occur with an improper gauge setting or if the rocker block means 80 were set improperly), can easily be overcome in the construction in accordance with the invention by providing suitable safety devices and overloading devices. For example, a primary means could be the cylinders 54 in combination with an electrical interlock means. In using the cylinders 54 as a safety overload means, the cylinders 54 would n-or-fally be placed under a low pressure and would be made responsive to an electrical interlock control which senses an overload condition and causes the pressurization of the cylinders 54 to expand them. This causes the rocker arms 50 to pivot in a direction to reduce the effect of the excessive rolling load which would have been transmitted to the outboard bearings 66. Actually, this serves to alter the path of rolling load so that the excessive portion of the rolling load is applied to the mill screw '74 instead of the outboard bearings '66 of the roll 22.

Other safety overload devices may be employed. For example, the roll latches 56 could be controlled to open in response to an overload. Also, other suitable interlock mechanisms may be provided to avoid the possibility of excessive undesired rolling loads. These will be apparent to those skilled in the art.

While the construction shown in FIGS. 1 and 2 is perhaps the most effective and versatile arrangement for achieving the self-energizing roll stiffening effect in accordance with the invention, this effect can be obtained in varying degrees by other mechanical configurations such as those shown in FIGS. 4, 5, 6 and 7. These figures are diagrammatic illustrations similar to that of FIG. 3 and illustrate the essential elements of the mill as they are associated with the upper backup roll 22, its bearings 30 and its outboard bearings 66.

It will be apparent that the roll can be considered to be a three-span beam on four supports for purposes of considering the forces applied thereto, and particularly, the roll crowning forces. This is the same as the arrangement shown in FIG. 3.

Referring to FIG. 4, it will be noted that the reaction beam is connected directly to each of the outboard bearings 66 and the inner bearing 3!} are aligned with the mill screws 74. This connection of the outboard bearings to the reaction beam serves to stiffen the roll by forcing the reaction beam to undergo a deflection compatible with the deflection 0f the roll as is shown by the dashed lines in this figure. Of course, the effectiveness of this arrangement is limited by the stiffness of the reaction beam and by the portion of the roll extending outwardly of the bearings 30. It will be apparent that by this arrangement the outboard bearing reaction is proportional to the rolling load P and that the reaction beam is connected to the outboard bearings so as to counteract the effect of the rolling load tending to bend the roll 22.

The arrangement shown in FIG. 5 is essentially the same as that disclosed in FIG. 4 except that there are provided a pair of bridge blocks 200 between the bearings 30 and the reaction beam 240. These bridge blocks 200 serve to apply the rolling load to the reaction beam 240 at locations spaced on either side: of the mill screws 74. This arrangement causes the bridge blocks 200 to induce a reverse bending of the reaction beam toward the condition shown by the dotted line in this figure. It will be apparent that this also is, in effect, a crowning load which serves to stiffen the roll against the action of the rolling load, Again, the outboard bearing loads are proportional to the rolling load.

The arrangement shown in FIG. 6 is also similar to that shown in FIG. 4 except that the mill screws 74 are positioned inwardly of the point of contact between the bearings 3t) and the reaction beam 340. This offset of the screws 74 causes a reverse bending of the reaction beam and the amount of the crowning force is dependent upon the amount of this offset, which is indicated by the dimension lines X in this figure. In other Words, the greater the spacing inwardly, the greater the amount of the crown reducing forces applied to the outboard bearings. Again, it will be noted that the rolling load is directed by way of the reaction beam 340 to the outboard bearings to 7 counter-bend the same against the action of the rolling load.

Referring now to FIG. 7 the construction shown therein is essentially the same as that shown in FIG. 6 except that the central portion of the reaction beam is removed to thereby, in effect, provide a pair of rocker arms 440. By this arrangement the rocker arms 440 serve to distribute the rolling load to the outboard bearings to counter-bend the same to maintain the proper crown control. Since the rocker arms 440 do not have to bend to achieve a crown control, the crown control is improved. Again, the crown controlling forces are proportional to the tolling load P and dependent on the amount of the offset dimension X.

It will be understood that the above description is illustrative and that changes may be made in the construction and arrangement of parts without departing from the scope of the invention as defined by the following claims.

We claim:

1. In a rolling mill, a pair of spaced housing members having windows therein, a pair of work rolls received in the openings of said housing members, a pair of backup rolls received in the openings of said housing members with one backup roll being associated with each work roll, journal bearing chocks for rotatably supporting end portions of said backup rolls in said windows of said housings, at least one of said backup rolls having extended ends outwardly of said journal bearing chocks therefor, a reaction beam extending between said windows of said housing members and adjacent said one backup roll and arranged to receive the rolling load from said one roll by way of said journal bearing chocks thereof, a pair of rocker arms, one of said rocker arms being arranged between said beam and each of said housing members for transmitting the rolling load applied to said beam from said one roll to said housing members, each of said rocker arms having portions extending outwardly of said housing members, force transmitting means positioned between said beam and each of said rocker arms for applying a force to each of said rocker arms from said beam at a location offset from the points where said rocker arms apply the rolling load to said housing members so as to urge said rocker arms to rock relative to said housing members, and means connecting the outer ends of each of said rocker arms to said extended ends of said one backup roll to thereby apply a crowning force thereto in response to the force tending to rock said rocker arms, said force tending to rock said rocker arms being responsive to the rolling load applied to said one backup roll and being proportional to this rolling load in accordance with the offset position thereof.

2. A rolling mill according to claim 1 including means mounting said force transmitting means for movement to various positions to vary the amount of offset and to vary the points at which said forces are applied from said beam to said rocker arms to thereby vary the crowning forces applied ot the ends of said one backup roll.

3. A rolling mill according to claim 2 wherein said force transmitting means comprises a rocker block assembly associated with each rocker arm, and means connected to said rocker block assembly for moving the same to various positions offset from the point of contact of said rocker arms with said housings.

4. A rolling mill according to claim 1 wherein the other of said backup rolls has extended ends outwardly of said journal bearing chocks therefor, and including means for controlling the crown of said other backup roll by transmitting rolling load forces to the extended end portions thereof.

5. A rolling mill according to claim 4 wherein said crown controlling means for said other backup roll comprises a reaction beam extending between said windows of said housing members and adjacent said other backup roll and arranged to receive the rolling load from said other backup roll by way of said journal bearing chocks thereof, a pair of rocker arms, one of said rocker arms being arranged between said beam and each of said housing members for transmitting the rolling load applied to said beam from said other roll to said housing members, each of said rocker arms having portions extending outwardly of said housing members, force transmitting means positioned between said beam and each of said rocker arms for applying a force to said rocker arms from said beam at a location offset from the point where said rocker arms apply the rolling load to said housing members so as to urge said rocker arms to rock relative to said housing members, and means connecting the outer ends of each of said rocker arms to said extended ends of said other backup roll to thereby apply a crowning force thereto in response to the force tending to rock said rocker arms.

6. In a rolling mill, a pair of spaced housing members providing opposed openings, a pair of material reducing rolls arranged to receive the rolling loads produced by the material being rolled, journal bearing means at end portions of said rolls for rotatably mounting the rolls in the openings in said housing members, at least one of said rolls having extended end portions outwardly of its journal bearing means, and crown controlling means including a mechanical force transmitting means constructed and arranged to receive the rolling load forces from said one roll and mechanically direct the rolling load forces through said force transmitting means to the extended end portions of said one roll in a direction to apply crowning forces thereto acting toward producing a negative crown thereon.

7. In a rolling mill, a pair of spaced housing members providing opposed openings, a pair of material reducing rolls arranged to receive the rolling loads produced by the material being rolled, journal bearing means at end portions of said rolls for rotatably mounting the rolls in the openings in said housing members, at least one of said rolls having extended end portions outwardly of its journal bearing means, and crown controlling means constructed and arranged to receive the rolling load forces from said one roll and direct the rolling load forces to the extended end portions of said one roll to control the crown thereof, said crown controlling means including a reaction beam extending parallel to said one roll and arranged to contact said journal bearing means thereof to receive the rolling load therefrom, a pair of rocker members mounted on said beam so as to transmit the rolling load applied to said beam to each of said housing members, each of said rocker members having a portion extending outwardly of said journal bearing means and connected to the extended end portions of said one roll, and means for transmitting the rolling load received by said beam to each of said rocker members at a location so as to urge the portions of said rocker members connected to said one roll toward pivoting about the load transmitting point between each rocker member and its associated housing member to thereby apply a crowning force to said ends of said one roll.

8. A rolling mill according to claim 7 wherein said last-named load transmitting means is mounted for movement to various load applying locations to vary the amount of the pivoting forces applied to said rocker members and thereby vary the amount of the crowning forces applied by said rocker members to said ends of said one roll.

9. In a rolling mill, a pair of spaced housing members providing opposed openings, a pair of material reducing rolls arranged to receive the rolling loads produced by the material being rolled, journal bearing means at end portions of said rolls for rotatably mounting the rolls in the openings in said housing members, at least one of said rolls having extended end portions outwardly of its journal bearing means, and crown controlling means constructed and arranged to receive the rolling load forces from said one roll and direct the rolling load forces to the extended end portions of said one roll to control the crown thereof, said crown controlling means including a pair of beam-like members each of which is mounted to receive at a medial portion the rolling load from said journal bearing means of said one roll, the outer end portions of said members being connected to said extended portions of said one roll, and each of said beam-like members being mounted adjacent a portion of one of said housing members in bearing contact therewith so as to transmit thereto the rolling load received from said journal bearing means, the location of the bearing contact of said beam-like members with said housing members being offset with respect to the location whereat said rolling load is applied to said members from said journal bearing means whereby said members act as rocker arms to apply crown controlling forces to the ends of said one roll, means for adjusting said locations Whereat said rolling load is applied to said beam-like members from said journal bearing means so as to be inwardly or outwardly of said locations of said bearing contact of said beam-like members with said housing members whereby a positive or negative crowning force may be applied.

10. A rolling mill according to claim 6 wherein said force transmitting means of said crown controlling means includes an adjustable lever means adjustable to direct said rolling load forces to the extended end portions of said one roll in different directions so as to produce either positive or negative crowning loads thereon.

-11. A rolling mill according to claim 7 wherein said last-named load transmitting means is mounted for movement to a load applying location producing the application of negative crowning forces by said rocker members to said ends of said one roll.

12. A rolling mill according to claim 8 wherein said last-named load transmitting means is mounted for movement to a load applying location wherein the pivoting forces applied to said rocker members are transmitted to said one roll to provide a negative crowning force.

13. A rolling mill according to claim 7 wherein said portions of said rocker members connected to the extending end portions of said one roll include power-operated means biasing said portions into an interconnecting position therewith and movable to a disconnecting position therefrom.

14. A rolling mill according to claim 7 wherein each of said rocker members has a portion extending inwardly of said journal bearing means, and including pressure actuated means for positioning said last-named portions and being responsive to the rolling loads transmitted to said rocker members.

References Cited UNITED STATES lPATENTS 3,364,715 l/l968 OBrien 72-245 3,373,588 3/1968 Stone 72237 3,442,109 5/1969 Diolot 72-240 3,461,705 8/1969 Neumann 72-243 3,507,138 4/1970 Neuber 72----237 CHARLES W. LANHAM, Primary Examiner B. J. OLLILA, Assistant Examiner US. Cl. X.R. 72-245 

